Lub rooj zaum lub tsheb yog cov khoom siv tseem ceeb ntawm cov tswv tsheb.Xaiv ib qho yooj yim, siv lub tsheb cushion raws caij nyoog yog qhov tseem ceeb tshwj xeeb.Tam sim no muaj tawv, tawv superfiber, tawv tawv, nylon, tshuaj fiber ntau, cov ntaub plaub tsiaj, polyester ntaub plaub thiab lwm yam ntaub ntawv sib txawv ntawm lub rooj zaum npog